Several protesters against a Chinese-backed mine in central Myanmar have been charged with holding an illegal demonstration, police said Wednesday.

They were among 100 activists who scuffled with police on Monday evening near the Chinese embassy in Yangon.

The protesters demanded the closure of the Letpadaung copper mine in the Sagaing region, where a female villager was shot dead during a clash with police 10 days ago.

The shooting has sparked a series of protests in Yangon and Mandalay as well as a running stand-off at the mine itself, which villagers say has been established for the benefit of a Chinese company at the expense of their land and the local environment.

"They protested in front of Chinese embassy on Monday. We opened the case against them as they breached the law," a police major in Yangon's Dagon township told AFP, requesting anonymity.

They face several charges including protesting without permission and criminal intimidation, the officer added.

Four of the protesters -- Naw Ohn Hla, Nay Myo Zin, Sein Htwe and Tin Htut Paing -- have been held in Yangon's notorious Insein prison since late Tuesday, police and activist sources confirmed.

The other three are still at large.

The protests were sparked by the death of Khin Win, in her 50s, on December 19 when police opened fire on protesters trying to stop the mine company from building a fence in territory disputed with local farmers.

The mine -- run by Chinese firm Wanbao as part of a joint venture with a major Myanmar military conglomerate --- has raised questions about Myanmar's reliance on investment from neighbouring China, which gave crucial political support to the former junta.

Opposition leader Aung San Suu Kyi has faced criticism for failing to use her moral authority on behalf of villagers near the mine.

Last year she chaired an investigation into the mine which recommended the government allow the project to continue to operate, inflaming anti-mine sentiment among local villagers.